Anderson P A, Alster J M, Clinton S K, Imrey P B, Mangian H J, Truex C R, Visek W J
J Nutr. 1985 Nov;115(11):1515-27. doi: 10.1093/jn/115.11.1515.
The effects of two carcinogens benzo[a]pyrene (BP) and symmetrical 1,2-dimethylhydrazine dihydrochloride (DMH), on plasma amino acid concentrations and on excretion of lipids and nitrogenous metabolites were studied in 7- to 8-wk-old male and female B6C3F1 mice. BP and DMH were fed at concentrations of 0.3125 and 0.0225 g/kg, respectively, in purified diets containing 10 or 40% soybean protein. Nutritional balances were measured over a 7-d period after 7 d of acclimatization. Females excreted less urea and more NH3 than males. Urinary urea-nitrogen, NH3, allantoin, uric acid and total urinary nitrogen were consistently higher in mice fed 40% protein than in those fed 10% protein. The increases in total and NH3 nitrogen paralleled the increase in nitrogen intake. Nitrogen of urea rose more, while that of allantoin and uric acid rose less, than nitrogen intake. Fecal lipid excretion, as a percentage of intake, was consistently higher in mice fed the 40% protein diets than in mice fed 10% protein. Plasma glycine and branched-chain amino acids were higher, but citrulline was lower, when the 40% protein diet was fed. Body weight gain was higher when the 10% protein diet was fed with BP than without it, but BP made no apparent difference in weight gain when the 40% protein diet was fed. BP interacted with dietary protein to influence the excretion of nitrogenous metabolites. In addition, BP feeding produced numerous BP X sex and BP X protein interactions for plasma amino acid concentrations. Compared to controls, feed intake and weight gain were, respectively, 8 and 61% lower in DMH-fed animals during wk 1, but no differences in intake or weight gain were found during wk 2. In contrast to BP, DMH had no significant effects on urinary or fecal nitrogen metabolites, except that urinary uric acid (relative to nitrogen intake) was 9% higher in DMH-fed mice than in controls. DMH-fed mice had 43% higher serum glutamate and 6% lower glutamine than controls.
在7至8周龄的雄性和雌性B6C3F1小鼠中，研究了两种致癌物苯并[a]芘（BP）和对称二盐酸1,2 - 二甲基肼（DMH）对血浆氨基酸浓度以及脂质和含氮代谢产物排泄的影响。BP和DMH分别以0.3125和0.0225 g/kg的浓度添加到含有10%或40%大豆蛋白的纯化日粮中。在适应7天后，进行为期7天的营养平衡测量。雌性小鼠排泄的尿素比雄性少，而氨比雄性多。喂食40%蛋白质的小鼠尿中尿素氮、氨、尿囊素、尿酸和总尿氮始终高于喂食10%蛋白质的小鼠。总氮和氨氮的增加与氮摄入量的增加平行。尿素氮的增加幅度大于氮摄入量，而尿囊素和尿酸氮的增加幅度小于氮摄入量。以摄入量的百分比计算，喂食40%蛋白质日粮的小鼠粪便脂质排泄始终高于喂食10%蛋白质日粮的小鼠。喂食40%蛋白质日粮时，血浆甘氨酸和支链氨基酸含量较高，但瓜氨酸含量较低。喂食10%蛋白质日粮并添加BP时，体重增加高于不添加BP时，但喂食40%蛋白质日粮时，BP对体重增加没有明显影响。BP与日粮蛋白质相互作用，影响含氮代谢产物的排泄。此外，喂食BP会产生许多BP×性别和BP×蛋白质对血浆氨基酸浓度的相互作用。与对照组相比，在第1周，喂食DMH的动物采食量和体重增加分别降低了8%和61%，但在第2周未发现采食量或体重增加有差异。与BP不同，DMH对尿或粪便中的氮代谢产物没有显著影响，只是喂食DMH的小鼠尿中尿酸（相对于氮摄入量）比对照组高9%。喂食DMH的小鼠血清谷氨酸比对照组高43%，谷氨酰胺比对照组低6%。
